Interstitial cystitis (IC) is a chronic inflammation or irritation of the urinary bladder wall with symptoms including urinary urgency, frequency, and often-severe pelvic and perineal pain which are similar to those of other bladder diseases, such as urinary tract infections (UTI), urethritis, urethral syndrome, trigonitis, prostatitis, dysuria, and nocturia. Thus diagnosis of the IC is difficult. After other similar bladder diseases have been ruled out a cystoscopic examination of the bladder wall may be carried out. If this examination reveals small petechial hemorrhages or larger Hunner's Ulcers, IC is usually diagnosed.
The cause of IC remains undetermined. Theories linking IC to bacterial infections are controversial as IC patients routinely test negative for infection in standard urinalysis. However, several studies have shown that symptoms are alleviated when IC patients are treated with antibiotics. Other theories point to defects in the epithelial permeability barrier of the bladder surface glycosaminoglycans (GAG). Once the bladder wall has lost the protective coating of GAG, irritative components and potentially pathogenic bacteria may lead to the inflammation or irritation associated with IC. Another line of research indicates that activated mast cells associated with pain and irritation are involved in the pathology of IC. Studies have shown that IC patients have an increased level of activated mast cells in tissues of their bladder walls.
Currently there is no treatment which permanently eliminates the symptoms of IC in the majority of patients. Drug therapy has been proven to be the most effective means of alleviating symptoms. Oral medications for IC include bladder-coating agents, antidepressants, antihistamines, antispasmodics and anesthetics. The effectiveness of oral medications is limited by the circulating concentration of the drug in the blood stream. To address this limitation, many IC patients elect to undergo a procedure called urinary bladder instillation, in which a therapeutic solution is pumped into the bladder through a urethral catheter. The solution, which may be composed of one medicine or a combination of medications, is held in the bladder for a “dwell time” before the bladder is voided. This procedure allows the treatment of the urinary bladder wall directly with high concentrations of medicine. Despite the drawbacks of a limited dwell time for the medication to take effect and the resulting mixing of medication with urine, bladder instillation remains among the most effective conventional treatments for IC.